As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON L/O FOUND EMERGENCY LIGHTS AT SEAT ROW 22D AFT INOP. SWAPPED BATTERY PACK, NO HELP. FOUND AFT RT POWER SUPPLY BAD. REMOVED POWER SUPPLY AND BATTERY PACK. BATTERY CHARGER HAS A BAD FUSE. REPLACED FUSE REF M/M. REPLACED BATTERY AND REINSTALLED CHARGER. TEST GOOD.